Title:
Rheological Behaviour of Alkali-Activated Slag Concrete
Author(s):
Francisca Puertas, María del Mar Alonso, Manuel Torres-Carrasco, Belen González Fonteboa, Iris González Taboada, Gemma Rojo, and Fernando Martínez-Abella
Publication:
Symposium Paper
Volume:
320
Issue:
Appears on pages(s):
6.1-6.12
Keywords:
Alkali activated concretes; compressive strength; mixing time; rheology
DOI:
10.14359/51701044
Date:
8/1/2017
Abstract:
This study compared waterglass- and NaOH-activated slag concrete (AASC) rheology to the behaviour in OPCC concrete. The effect of mixing time on fresh concrete rheology was also assessed. A rotational rheometer was used to apply shear stress to the materials to determine static and dynamic yield stress
at 15, 30, 45 and 60 min of age. Concrete strength and porosimetry were determined to relate rheology to hardened concrete behaviour.
The results indicate that slump and rheological behaviour of OPCC and AASC are different, scpecially when the alkaline activator is waterglas (AAS WG). The mixing protocol appeared to affect concrete rheology (fresh behaviour) more than its strength (hardened behaviour). In AASC WG, both rheological and mechanical behaviour improved at longer mixing times.
Related References:
1. Palomo, A., Krivenko, P., Kavalerova, E., and Maltseva, O. 2014, “A review on alkaline activation : new analytical perspectives”, Materiales de Construcción. 64, 315, e022.
2. Pacheco-Torgal, F., Labrincha, J.A., Leonelli, C., Palomo, A., and Chindaprasirt, P. 2015,Handbook of Alkali-activated cements, mortars and concretes, Woodhead Publ. series in civil and structural engineering.
3. Provis, J.L., Palomo, A., and Shi, C. 2015, “Advances in understanding alkali-activated materials”, Cem. Concr. Res. 78, 110–125.
4. Jiang, M., Chen, X., Rajabipour, F., Asce, A.M., Hendrickson, C.T., and Asce, D.M. 2014, “Comparative Life Cycle Assessment of Conventional , Glass Powder and Alkali-Activated Slag Concrete and Mortar”, J. Infrastruct. Syst. 20,
5. Fernández-Jiménez, A., Palomo, J.G., and Puertas, F. 1999, “Alkali-activated slag mortars Mechanical strength behavior” Cem. Concr. Compos. 29, 1313–1321.
6. Aydin, S., and Baradan, B. 2014, “Effect of activator type and content on properties of alkali-activated slag mortars” Compos. Part B Eng. 57, 166–172.
7. Torres-Carrasco, M., Tognonvi, M., Tagnit-Hamou, A., Puertas, F. “Durability of alkali-activated slag concretes prepared using waste glass as alternative activator” ACI. 112, 2015, 791–800.
8. Chi, M. 2012, “Effects of dosage of alkali-activated solution and curing conditions on the properties and durability of alkali-activated slag concrete” Constr. Build. Mater. 35, 240–245.
9. Duran Atis, C., Bilim, C., Çelik, Ö., and Karahan, O. 2009, “Influence of activator on the strength and drying shrinkage of alkali-activated slag mortar” Constr. Build. Mater. 23, 548–555.
10. Palacios, M., and Puertas, F. 2007, “Effect of shrinkage-reducing admixtures on the properties of alkaliactivated slag mortars and pastes” Cem. Concr. Res. 37, 691–702.
11. Ye, H., and Radllinska, A. 2016, “Shrinkage mechanisms of alkali-activated slag” Cem. Concr. Res. 88, 126–135.
12. Puertas, F. 1995, “Cementos de escorias activadas alcalinamente : Situación actual y perspectivas de futuro” Mater. Construcc. 45, 239, 53–64.
13. Fernandez-Jimenez, A., and Puertas, F. 2001, “Setting of alkali-activated slag cement. Influence of activator nature” Adv. Cem. Res. 13, 115–121.
14. Palacios, M., Banfill, P., and Puertas, F. 2008, “Rheology and setting of alkali-activated slag pastes and mortars: Effect of organic admixture” ACI Mater. J. 105, 140–148.
15. Shi, C., and Day, R.L. 1995, “A calorimetric study of early hydration of alkali-slag cements” Cem. Concr. Res. 25, 1333–1346.
16. Palacios, M., 2006, “Empleo de aditivos orgánicos en la mejora de las propiedades de cementos y morteros de escoria activada alcalinamente” PhD Tesis UAM Madrid.
17. Puertas, F., Varga, C., and Alonso, M.M. 2014, “Rheology of alkali-activated slag pastes. Effect of the nature and concentration of the activating solution” Cem. Concr. Compos. 53, 279–288.
18. Palacios, M., and Puertas, F. 2005, “Effect of superplastisizer and shrinkage reducing admixtures on alkaliactivated slag pastes and mortars” Cem. Concr. Res. 35, 1358–1367.
19. Yang, K.-H., Song, J.-K., Ashour, A.F., and Lee, E.-T. 2008, “Properties of cementless mortars activated by sodium silicate” Constr. Build. Mater. 22, 1981–1989.
20. Carro-López, D., González-Fonteboa, B., de Brito, J., Martínez-Abella, F., González-Taboada, I., and Silva, P. 2015, “Study of the rheology of self-compacting concrete with fine recycled concrete aggregates” Constr. Build. Mater, 96, 491–501.
21. Alonso, M.M., Gismera, S., Blanco, M.T., Lanzón, M., Puertas, F. 2017, “Alkali-activated mortars: Workability and rheological behavior” Const. Build Mater, 145, 576-587
22. Tattersall, G.H., Banfill, P. 1983. “The Rheology of Fresh Concrete”, Pitman Books Limited, Great Britain.
23. Mahmoodzadeh, F., and Chidiac, S.E. 2013, “Rheological models for predicting plastic viscosity and yield stress of fresh concrete” Cem. Concr. Res. 49, 1–9.
24. Puertas, F., Palacios, M., Manzano, H., Dolado, J.S., Rico, A., and Rodríguez, J. 2011, “A model for the CA-S-H gel formed in alkali-activated slag cements” J. Eur. Ceram. Soc. 31, 2043–2056.